Granted Patent
Utility
US 3,982,073 · App. 05/545,050
System for measuring the duration of a telephone call
Inventors:
Gary L. Baltzer, Duane A. Desler, George Pappas
Patented Case
View Patent ↗
Granted: Sep 21, 1976
Filed: Jan 29, 1975
Inventors
Gary L. Baltzer
Duane A. Desler
George Pappas
Assignee (at issue)
Western Electric Company, Inc.
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.